Reactive liquid polymers poly

Mixtures of liquid vinyl monomers and polymer powders serve as a basis for a special group of engineering materials. Vinyl acetate and acrylonitrile monomers are injected into polymer powders to accelerate swelling and gel formation. Styrene is added to improved the molding characteristics of reactive mixtures. Polystyrene, poly(vinyl acetate), poly(vinyl chloride), etc. are the most commonly used polymer powders. 

This reaction between poly sulfide liquid polymers and epoxy resins is catalyzed or promoted by organic amine compounds. Although a considerable number have been evaluated, final selection has narrowed the list down to a few practical catalysts among which ate DMP-30 , Rohm and Haas) (tri-dimethylamino-methyl phenol), DET (diethylenetriamine), and BDA (benzyldimethylamine). The amine catalysts are used in a fairly high ratio, in most cases 10% based on weight of the epoxy resin. Because of the coreaction of primary amines such as DET, they are more properly classified as reactive hardeners. The general reaction of a polysulfide liquid polymer, an epoxy resin, and a primary amine hardener is ... 

Many common polymers, polymeric additives and lubricants oxidise so rapidly after impact in liquid oxygen that they are hazardous. Of those tested, only acrylonitrile-butadiene, poly(cyanoethylsiloxane), poly(dimethylsiloxane) and polystyrene exploded after impact of 6.8-95 J intensity (5-70 ft.lbf). All plasticisers (except dibutyl sebacate) and antioxidants examined were very reactive. A theoretical treatment of rates of energy absorption and transfer is included [1], Previously, many resins and lubricants had been examined similarly, and 35 were found acceptable in liquid oxygen systems [2],... 

Besides in the liquid phase, some polyreactions are also performed in the solid state, for example, the polymerization of acrylamide or trioxane (see Example 3-24). The so-called post condensation, for example, in the case of polyesters (see Example 4-3), also proceeds in the solid phase. Finally, ring closure reactions on polymers with reactive heterocyclic rings in the main chain (e.g., poly-imides, see Example 4-20) are also performed in the solid state. 

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